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Pharmaceutics ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1534
Author(s):  
Ekaterina Silina ◽  
Victor Stupin ◽  
Natalia Manturova ◽  
Vitaly Vasin ◽  
Konstantin Koreyba ◽  
...  

We studied the efficacy of using mesenchymal stem cells (MSC) and a polymeric compound (based on chitosan and cellulose with integrated cerium dioxide nanoparticles (PCCD)) in wound healing, and to compare the effects with various invasive and external drugs used for the same purpose. Two wounds were made on the backs of each of 112 Wistar rats, removing the skin. Eight groups were studied: Control_0—intact wounds; Control_ss—0.9% NaCl injections; MSC injections; Control_msc—intact wounds on the opposite side of the body from the MSC group; external application of the PCCD; external application of a combination of the drugs PCCD + MSC; DCh –ointment Dioxomethyltetrahydropyrimidine + Chloramphenicol; and DHCB—injections of a deproteinized hemoderivative of calf blood. After 14 days, we evaluated the state and size of the wounds, studied the level of microcirculation, performed a histological study, and identified and counted the different types of cells. The most effective remedy was combination PCCD + MSC. The treatments in the PCCD and MSC groups were more effective than in the DHCB and DCh groups. Invasive drugs and DCh slowed the regeneration process. DHCB did not affect the rate of healing for acute wounds without ischemia during the first week. The proven efficacy of developed polymeric compounds demonstrates the feasibility of further studies in clinical practice.


2021 ◽  
Vol 22 (1) ◽  
pp. 35-43
Author(s):  
Hamide Filiz Ayyildiz

Free fatty acid, peroxide value , conjugated diene and triene, chlorophyll, β-carotene, fatty acid composition, triglyceride, tocol (tocopherol and tocotrienol) compositions, sterol, wax and total polymeric compound amounts of cold pressed Ficus carica seed oil were evaluated by using chromatographic and spectrometric methods in this study. While the % free fatty acid of cold pressed ficus carica seed oil was 0.76±0.06, the peroxide value was found as 1.06 ± 0.09 meqO2/kg. It also had low content of conjugated diene and triene amounts, chlorophyll, wax and total polymeric compounds. The obtained results demonstrated that cold pressed ficus carica seed oil had rich linolenic and linoleic acid, and contained high amounts of Linoleic- Linolenic- Linolenic, Linolenic- Linolenic- Linolenic, Olenic- Linoleic– Linolenictriglycerides. Cold pressed ficus carica had a high content of β-carotene (4114.9 ppm), total tocol (1006 ppm) and sterol (7250.83 ppm). The obtained results showed that ficus carica seed oil is a product with superior properties due to its high nutritional value and beneficial phytochemicals. Therefore this oil can be an alternative to vegetable oils and used as a medical product.


Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 937
Author(s):  
Fabio Ippolito ◽  
Gunter Hübner ◽  
Tim Claypole ◽  
Patrick Gane

Adjusting the thermal response properties of a polymeric compound can significantly improve the usability in a selective laser-sintering process. As previously shown, combining a precise amount of coarse and narrow size distribution fine calcium carbonate fillers results in a potential optimization of the thermal properties of a polyamide 12 matrix. Additionally, up to 60% of the normally associated lost ductility can be re-gained by surface modification, thus functionalizing the filler. To optimize the functionality further this study combines a precisely defined particle size ratio of fillers adopting a specially selected surface modification using amino hexanoic acid. Morphology of the carbonate filler was also investigated. The range of effect of each parameter on the thermal response and mechanical properties was studied. The results show that the thermal properties have large potential to be optimized, without reducing the ductility significantly, by adjusting the morphology and size ratio of coarse and fine filler particles. The compound properties were demonstrated using a twin-screw extruder, indicating the potential for producing a preparate composite for additive manufacturing.


Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1203
Author(s):  
Manuel Álvarez ◽  
Daniel Ferrández ◽  
Carlos Morón ◽  
Evangelina Atanes-Sánchez

This paper shows the characterization of a new lightened gypsum-based material for use in buildings. A plaster material has been designed with a polymeric compound based on polyvinyl acetate, bicarbonate and a boric acid solution, which reduce the density and thermal conductivity by up to 20% and 30%, respectively. In addition, tests have been carried out with the lightened plaster material reinforced with glass (GF), basalt (BF), polypropylene (PPF) and wood (WF) fibers. A significant improvement in mechanical properties was achieved. All samples obtained resistance values greater than 2 MPa in flexion and 3 MPa in compression. Physico-chemical analysis were also carried out. The study is completed with a statistical analysis, where confidence intervals have been obtained for the mean at 95% confidence for each of the physical properties studied.


Crystals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 48
Author(s):  
Jeannette Carolina Belmont-Sánchez ◽  
María Eugenia García-Rubiño ◽  
Antonio Frontera ◽  
Josefa María González-Pérez ◽  
Alfonso Castiñeiras ◽  
...  

We synthesized and studied the polymeric compound {[Cu2(µ4-EDTA)(Him)2] 2H2O}n (1). The single-crystal structure is reported along with an in depth characterization of its thermal stability (TGA), spectral properties (FT-IR, Vis-UV and RSE), and magnetic behavior. The crystal consists of infinite 2D-networks built by centrosymmetric dinuclear motifs, constructed by means of a bridging anti,syn-carboxylate group from each asymmetric unit. Each layer guides Him ligands toward their external faces. They are connected by intermolecular (Him)N-H···O(carboxylate) bonds and antiparallel π–π stacking between symmetry related pairs of Him ligands, and then pillared in a 3D-network with parallel channels, where disordered water molecules are guested. About half of the labile water is lost from these channels over a wide temperature range (r.t. to 210 °C) before the other one, most strongly retained by the cooperating action of (water)O1-H(1A)···O(carboxylate) and (water) O1-H(1B)···π(Him) interactions. The latter is lost when organic ligands start to burn. ESR spectra and magnetic measurements indicated that symmetry related Cu(II) centers connected by the bridging carboxylate groups behave magnetically not equivalently, enabling an exchange interaction larger than their individual Zeeman energies.


Molbank ◽  
10.3390/m1179 ◽  
2021 ◽  
Vol 2021 (1) ◽  
pp. M1179
Author(s):  
Eleftherios Halevas ◽  
Antonios Hatzidimitriou ◽  
Barbara Mavroidi ◽  
Marina Sagnou ◽  
Maria Pelecanou ◽  
...  

A novel Cu(II) complex based on the Schiff base obtained by the condensation of ortho-vanillin with gamma-aminobutyric acid was synthesized. The compounds are physico-chemically characterized by elemental analysis, HR-ESI-MS, FT-IR, and UV-Vis. The complex and the Schiff base ligand are further structurally identified by single crystal X-ray diffraction and 1H and 13C-NMR, respectively. The results suggest that the Schiff base are synthesized in excellent yield under mild reaction conditions in the presence of glacial acetic acid and the crystal structure of its Cu(II) complex reflects an one-dimensional polymeric compound. The molecular structure of the complex consists of a Cu(II) ion bound to two singly deprotonated Schiff base bridging ligands that form a CuN2O4 chelation environment, and a coordination sphere with a disordered octahedral geometry.


2021 ◽  
Vol 229 ◽  
pp. 01054
Author(s):  
Ouafae Ninis ◽  
Mohammed Bouachrine ◽  
Mustapha Abarkan

The copolymer based on Poly(3, 4-Ethylene dioxythiophen) and Poly(n-Vinylcarbazole) was characterized by FTIR and Raman spectroscopy. The temperature and frequency evolutions of dielectric parameters are also plotted and studied. The dependence of ε” on the temperature shows relaxation process for studied copolymer especially with frequencies about 1kHz for the temperatures: 90°C < T < 118°C. The values of ε’∞, ε’’MAX, relaxation time and DC conductivity corresponding to the copolymer are also determined with the aim to provide dielectric analysis involving vital information about this new polymeric compound.


2020 ◽  
Vol 34 (2) ◽  
pp. 285-293
Author(s):  
S. J. E. Ntum ◽  
E. N. Mainsah ◽  
A. Mohamadou ◽  
J. Raftery ◽  
P. O’Brien ◽  
...  

The title compound, N-(2-pyridylmethyl)-L-alanine) zinc(II), [Zn(C10H11N3O2S)], a coordination polymer derived from the mixed ligands, N-(2-pyridylmethyl)-L-alanine (HL1) and ammonium thiocyanide (L2) has been synthesized and characterized by IR spectroscopy, 1H-NMR, elemental analysis, thermogravimetric analysis and single crystal x-ray structure determination.The single crystal X-ray structure analysis of the title compoundreveals a molecular polymeric compound that crystallizes in the orthorhombic crystal system and P2(1)2(1)2(1) space group. The ligand acts as a bridge between adjacent zinc(II) centres, each of which adopts a five-coordinate geometry.  Zinc bonds to two N atoms and one O atom of HL1, one N atom of L2 and one O atom of another HL1 ligand. This is confirmed by IR spectroscopy. Thermogravimetric analysis shows a one-step decomposition of the complex to leave a zinc sulfide residue.                     KEY WORDS: Zinc(II), N-(2-pyridylmethyl)-(L)-alanine) ligand, Isothiocyanate, Coordination polymer, Single crystal structure   Bull. Chem. Soc. Ethiop. 2020, 34(2), 285-293 DOI: https://dx.doi.org/10.4314/bcse.v34i2.7


Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4102
Author(s):  
Guozhao Zhang ◽  
Haiwa Zhang ◽  
Sandra Ninet ◽  
Hongyang Zhu ◽  
Keevin Beneut ◽  
...  

The compression of ammonium azide (AA) has been considered to be a promising route for producing high energy-density polynitrogen compounds. So far though, there is no experimental evidence that pure AA can be transformed into polynitrogen materials under high pressure at room temperature. We report here on high pressure (P) and temperature (T) experiments on AA embedded in N2 and on pure AA in the range 0–30 GPa, 300–700 K. The decomposition of AA into N2 and NH3 was observed in liquid N2 around 15 GPa–700 K. For pressures above 20 GPa, our results show that AA in N2 transforms into a new crystalline compound and solid ammonia when heated above 620 K. This compound is stable at room temperature and on decompression down to at least 7.0 GPa. Pure AA also transforms into a new compound at similar P–T conditions, but the product is different. The newly observed phases are studied by Raman spectroscopy and X-ray diffraction and compared to nitrogen and hydronitrogen compounds that have been predicted in the literature. While there is no exact match with any of them, similar vibrational features are found between the product that was obtained in AA + N2 with a polymeric compound of N9H formula.


Author(s):  
Anjana S ◽  
Dr. Shaji P Thomas

Natural fibers such as hemp, sisal, jute, cotton,flax and broom are the most commonly used fibers for the reinforcement of polymers. These bio fillers are used in polymeric compound because of its low cost and bio degradable nature. This review gives the information about bio fillers rice husk and egg shell used in polymer technology and importance of this bio fillers in science and technology area.


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